In short, organic soil hangs onto more of its “good stuff” for a longer period of time, while chemical systems can lose the “good stuff” more quickly

What a brilliant synopsis of how a healthy soil works. This report by the Rodale Institute is the culmination of a 30 year trial comparing organic and conventional farming systems in the US and shows that organic systems outperform conventional ones over a wide range of parameters both environmental and financial. It gives a positive view of the benefits organic farming systems deliver in making farming systems more robust in sub-optimal conditions and should be read and taken seriously by policy makers and agriculturalists as we look at making food production better suited for the 21st centuary.

The US systems studied are directly comparable to those employed in the UK but the principles of healthy soils are surely universal. Improved soil carbon levels act as a reservoir of both moisture and nutrients and a biologically active soil can make these available to growing plants. Whether the soil is lacking moisture or inundated with moisture the higher carbon levels seen in organic soils makes them better able to cope with both scenarios.

Read the full report. It is an excellent arguement for greater focus on organic and agro-ecological farming systems. The Rodale Institute 30 Year Trial Report